This prospective longitudinal study of the etiology of alcoholism began in its second year to accept its first participants, participants selected through random telephone interviews, followed by home visitis where consent was obtained to a full day's on-site visit. The participants, expected to number 325 in this budget year, provide personal data in the social-cultural, psychological, cognitive-perceptual and biological realms; the particular measures used were chosen to highlight differential responses hypothesized to play an etiological role in drinking problems. The study is projected to enlist over 5,000 adolescents to be seen at 3-year intervals until the age of 24, and thereafter at 6-year intervals. An additional 600 new participants are slated to be interviewed and tested in year 3. About 8,600 telephone interviews were necessary to obtain 325 subjects, representing more than one-third of age-eligible respondents; analysis of demographic and other data from this process reveals that participants do not differ from age-eligible non-participants, nor from the larger sample of ineligibles. This study is expected to identify predictive factors predisposing to alcohol abuse and alcoholism: such identification should make possible targeted intervention of persons at risk, prevention of development of alcoholism its goal. In the shorter term, the knowledge gained of the nature and extent of alcohol problems experienced by adolescents as they transit toward adult drinking patterns will help in the formulation of appropriate prevention strategies for specific problem complexes.